Pressure regulator valves can be used to decrease pressure in a fluid transmission line system. Typically, the pressure regulator valves include a valve housing and these valve housings often have exterior surfaces or portion of exterior surfaces that are contoured with complex curvature (e.g., curves having more than one radius of curvature). For example, the known pressure regulator valve 10 of FIG. 1 includes a valve housing 12 such a contoured exterior surface 14. A separate outlet member 16 may be secured to a portion of the valve housing 12 such that a first end flange 18 has a mating surface that is machined to correspond to the shape of the contoured exterior surface 14, as illustrated in FIG. 1. The outlet member 16 has a second end flange 20 adapted to be coupled to a portion of the transmission line (not shown), and fluid flows from through the interior of the outlet member 16 from a valve control element (not shown) disposed within the valve housing 12 to the transmission line.
In some applications, the pressure regulator valve 10 may generate a great deal of noise as fluid expands within the outlet member 16. Accordingly, a sound treatment device 22 may be employed to attenuate the noise level, as illustrated in FIG. 2. Typically, the outlet member 16 is removed by the end-user and the sound treatment device 22 is secured to the valve housing 12. The sound treatment device 22 may include a housing 24 and a plurality of sound reducing elements disposed within an interior of the housing 24. For example, the plurality of sound reducing elements may include a plurality of springs 26 disposed within a retaining element and/or one or more perforated sounds plates 28 disposed normal to the direction of fluid flow. As known in the art, such sound reducing elements gradually reduce pressure in the fluid to reduce noise. Because the sound treatment device 22 engages the valve housing 12 in the same manner as the outlet member 16, a first end flange 30 has a mating surface that is machined to correspond to the shape of the contoured exterior surface 14. So configured, the contoured mating surface of the first end flange 30 of the sound treatment device 22 is difficult and expensive to machine. Because the outlet member 16 is replaced with the sound treatment device 22, the outlet member 16 is discarded, thereby inefficiently wasting a precisely machined part.